Fluid pressure system



" July zo, 194s. J. KELLQGG 2,445,437

FLUID PRESSURE SYSTEM Filed Aug. 21. 1946 5 Sheets-Sheet l n al July 2o, 0194s. J. KELLOGG FLUID PRESSURE SYSTEM Filed Aug. 21. 1946 5 Shegts-Sheet 2 July 20, 1948. J. KELLOGG 2,445,437

AFLUID PRESSURE SYSTEM Filed Aug. 21. 194s sheets-sheet s 'a INVEN TOR.

1.0 B "IJ-OSey//zelloyj July zo, 194s. Y J.'.KE| OGG 2,445,437

FLUID PRESSURE SYSTEM Filed Aug. 21. 1946 f5 sheets-sheet 4 J. KELLoGcs,`

FLUID PRESSURE SYSTEM July 2o, 194s.

5 Sheets-Sheet 5 Filed Aug. 21. 1946 Patented July 20, 1948 FLUID PRESSURE VSYSTEM Joseph Kellogg, Milwaukee, Wis., assignor; to

Nordberg Manufacturin Wis., a corporation of ,This invention relates to fluid pressure systems and more particularly to `a fluid pressure system for use in connection with hydraulicbrakes, or the like, and is an improvement on the. application of Joseph Kellogg, Serial No. 612,932, led August 27, 1945. I

Thefluid pressure system shownin co-pending application Serial No. 612,932 was built with a horizontal tank, the sump tank directly underneath and the motorand pump arranged between the sump tank and the pressure tank. It has been found thatV this construction, while thoroughly workable, occupies more space than necessary and it is therefore one object-of the present invention to provide an oil pressure tank which will be less cumbersome and less bulky than those nowinuse.

Another object of the invention is to provide an oil pressure tank for fluid brakes, or the like, which will be more economical to manufacture.A

A further object is to provide an oil pressure tank for hydraulic brakes, or the like, which can be more readily serviced. 1 I

Other objects will become apparentupon considering the following specification whichwhen taken in conjunction with the accompanying drawings illustrate a preferred form of the invention.

In the drawings:

Fig. 1 is a top plan View of a pressure .tank embodying the invention andfshowing the `pumps and motors mounted thereon; 1

Fig. 2 is a cross-sectional View showing the interior of the tank;

Fig. 3 is an .elevational view of the oil pressuretank shown in Figs. 1 and 2;

Fig. 4 is a top plan view -similar to Fig. 1 showl ing a modified form of the invention;

Fig. 5 is a cross-sectional view showing the interior of the tank as seen in Fig. 4; i

Fig. 6 is an elevational view of the modification shown in Figs. 4 and 5;

Fig '7 is a vertical cross-sectional view of a fragment of the tank showing the float controlV valve in vertical cross-section; and

Fig. 8 is a cross-section taken on the line 8 8 of Fig. "I, looking in the direction of the arrows.

Referring to the drawings, andparticularly to Figs. 1, 2 and 3, the invention comprises a cylindrical pressure tank IIJ mounted co-axially on-a sump tank I I. The pressure tank II) has vertical, cylindrical walls and is closed at the bottom by a plate I2 and at the top by a plate I3. A plurality of reinforcing posts I6, six of which are shown in Figs. 1 and 2, 4are spaced around the g COmpany, Milwaukee,

Wisconsin" v Application August '21, 1946, Serial No. 692,009

' 4 claims. (cx. 10a- 6) 2 v interior of the tank II)I and joined integrally between the plate I2 and the plate I3.

A standpipe I8 is mounted between the plate I2 and the plate I3 and is integrally joined to both plates by welding to form a central support for the tank comparable to the posts IIS. Apertures I9 are formed in the standpipe I8 above thev normal maximum level of liquid in the `tank I0. Vents 20 are formed inthe upper end of the standpipe I8 to permit the free passage of air into and out of the standpipe.

The pumping equipment which is mounted on the plate I3 of the tank I0 may comprise (Figs. 1 and 2) a pair of pumps 23-23 driven by electric motors 21E-T25 directly connected thereto. Magnetic starters 2'I-2'I are adapted to start the motors .when the pressure in the tank is below a desired minimum and shut olf the motors when the pressure is above a desired maximum. 'I'he starters 21%21 are actuated by pressure switches 29-28 responsiveto pressure within the tank.

The liquid is drawn by the pumps 23-23 from the sump tank II through intake pipes 3.0-30 into the inlet side of the pumps, and is discharged from the pumps 23--23 through discharge pipes 32-32.

The intake pipes 30--30 are entirely Within the peripheral walls of the tanks I0 and II and pass upwardly from a screened opening 33 adjacent the bottomof the sump tank I I, through the tank II, through the bottom I2 of the tank I0, upwardly through the tank I0, through the plate I3 and to the pumps 23-23. The pipes 30 are welded or otherwise permanently fixed in both plates I2` and I3 so as to prevent the escape of pressure therearound.

The` discharge pipes 3.2--32 lead from the discharge vside of the pumps 23-23 through check valves 35535, thence downwardly through the plate I3 and through tank I0, and enter the bottom of the standpipe I8 on the opposite sides thereof tangentially to the radius of gyration of the standpipe. The check valves 35 prevent back flow through the pumps 23-23.

The liquid from the pumps therefore passes downwardly and enters the standpipe I8 in a horizontal tangential direction causing the liquid to assume a swirling motion and form a vortex, the swirling motion causing any air in the liquid to separate therefrom. The air and liquid leave the standpipe I8 through the apertures I9 in the side of the standpipe, the apertures being above the maximum liquid level in the tank Il). Any air that mightbetrapped in the standpipe bya The valve comprises a body 46 having passages therethrough, to be more fully described below, and a plunger 48 adapted to uncover the various apertures as the liquid rises in the tank. The

plunger 48 is controlled by afloat 50 Vwhich moves j the plunger in accordance with the liquid"lei/'e1A in the tank.

When there is no oil in the tank I0 or the oil is below a predetermined minimum, the plunger 48 is forced to the extreme right as seen in Fig. 8. In this position' air is free to flow-from the interior of the tank i0; through the' Vent pipe 52', through central aperture 5d infth'e" valve body 4-8, into an aperture 56 in thevalve'body surrounding the aperture*5t,ithroughpassages 58 and 50" and through a pi'pef'-- to lthe top ofthe sump tankl Il from whenceV it is vented to the atmos- .phere through openings l5` Ii As the liquicl'levelrises4 above'the predeterminedA minimum the plungerllV closes ofi the passage 52 from the passage 56 and allows-the air pressure to l build up withinv the tank l0' as' the' liquid level" continues to rise.

When the liquid level rises" above the predetermined minimum the plunger i8 opens apassage 63 (Fig. 8) which permits air toflow fromA within the'tank I I Where'fit is at atmosphericpressure, through a pipe 65', through the passage 63E in theV valvebody 46, past the plunger 48; thoug'hapipevr ii'I,4 through' a `T` 69, through pipes4 10" and If and into one or both inlet :pipes 30fof the' pumps 23e-23; The pumps' 2323-=therefore draw in both liquid and air when the -l'eve'l of liquidi inV the tank |0` is above a predefterrinineclA minimum and discharge a mixture of lid-uidv and air into thev standpipe I8.

A sight gauge 'I5is provided on the exterior' of the tank I0 to indicate visually theoil-level there'- in. Oil Afrom the tank I0 mayv beA withdrawnv through a delivery pipe/'I6 and deliveredftoahy'- draulio brake actuator (not shown). Gilis returned from the hydraulic brake actua-tor andl enters the sump tank II 'through an opening 18;.

vThe form ofthe invention shown in Figsf, 5,

and' is suitable to smaller installations orA instalfl lations requiringv less frequent use of the hoist:`

In Figs. 4, 5 and 6 acylindrical sump tank |00 hasa cylindrical pressure tank Ill-'f mounted.' a5:-

ially` thereon. The pressure tank'is reinforced by a' concentric standpip'e `I'03 'which i's secured tok both the top i'and'bottoin' |06" of' the' :pressure tank IUI'.

oilV from me slump tank@ Int'- fiow's upwardly" through an inlet pipeV IIlBVintotheiilt side oi a pump I I0, and is discharged from tliepu'mp II'U under increased pressure; through a-.pipe H2. The

pipe IIZ passes into the tan-k It and discharges the oil into the ibottoni oftheV stanclpipe IEt sthat thek oil enters the standpipe substantivllyv tan-v gentially to the radius of gyrationofthe vinterior ofthe standpipe.

Air i-s-separated from the liquid entering the standpipe in thenia-ritter'Y described above; and is' dischargedl either through openings- H or throughventopenings H6;- Tlie'liqu-id, free' ofA when 4 air, is discharged from the standpipe |03 through the openings H5, the openings I|5 being above the normal desired maximum oil level in the tank IOI.

Air pressure within the tank |0I is built up and maintained by a float control valve I II, which is identical in construction and operation to the valve 4i used" in the pressure' tank shwnin Figs. 1,- 2-and 3' and shown iti-detail" in Figs'. '7 and 8. When the level of oil inthe tank |0| is above the desired minimum the air valve opens permitting air to flow from the sump tank |00 through a pipe |22, past the valve II'I, through a pipe |23 and intovtheinlet side of* the pump IIO. When the oil? level rises above a desired maximum oil is returned from the tank |0I through the valve H'I and the pipe |24 to the sump tank |00.

The motor ||8 which operates the pump ||0 is controlled by a starter I I9 and a pressure switch |20. The pressure switch operates at apredetermin'ed minimum pressure within' theta'kinl vu start the' motor' H8 and operates at av lietli-ite'-v and returned from the brake actiiating-rrizilae` nismthrough'a-pipe lz'to the sump tanki'u'. -A

sight gage' #2l is provided to visu'z'ai'llx'rA indicate tlielilu'dlvel in thetank.

pei'din In operationthe motors 25 mayA started with' the oill inl the tank I0 below the desired predeterminedhmiimurn and the air pressure within" the ventrtube 52 and thepipe. iissoonasftliel level of: liduidinthe' tank I0 rises above' thepre'e determined minimum the passage through tlriz vent tube 52 to atmosphere is closedby the/valve plunger 148 so that no* further air is vented.

The liqi'iid'v entering the intake of' the pumps 23-23 is discharged fromthe pnmps23$23funder considerable pressure and: passes downwardly through the pipes 32-32 and enters' thes'tandpipe tangentiall'y to'itlie radius oi? gyration of theiterior area of the standpipe.. .The'ent'ering liquid' therefore assumes a `whirling movement" in the standpipe I8 which causesavortefx tofbe iormedfv ing liquid causes the'he'avy liquidI toV be'thrown" to l the" outside, pei-unitingy anyy air in soiution' to pass out through the surface oiv the'tort'e and` enterl the-tank t0* th-rou'glix either' theports I3 or the ports 20; f

As liquid is puiiiped-intoitl'ie Stahdipipe fftli' vortex: nsesuntii the upper lever risesabove" the ports le, at which' time the air .free liquid' is discharges-out-tnfougntne pons le -intuuieitody Asme lever ef peut@ in me tanni It' continues meneame passage segmrdegh ehezpipesi T 68 and one or both of the pipes 10 and 1|, to enter the inlet pipes 30-30 of the pumps 23-23. When the passage Way 63 is opened by the plunger valve 48, the pump draws in both air and liquid, the mixture of air and liquid being discharged through the pipe 32 into the standpipe I8, Where it is separated by centrifugal action as outlined above.

As air continues to be pumped with the liquid, the air pressure within the tank l0 continues to build up, and the liquid level continues to rise until it reaches a desired maximum. When the liquid level reaches a desired maximum the plunger 48 moves out to the position shown in Fig. 7, opens the passages 51, 56, 58, 59 and permits oil to pass out through the pipe 60 and back into the sump tank Il Thus the liquid level in the tank I0 remains substantially constant at the maximum desired liquid level while continued pumping of air and liquid serves only to increase the pressure within the tank l 0.

When the pressure Within the tank I0 reaches a predetermined maximum, the pressure switches 28-28 shut oi' both motors 25-25 to stop further pumping.

When, due to use of the liquid in the tank, the pressure drops a predetermined amount, one of the pressure switches 28 will cut in one pump 23 to rebuild the oil in the tank. Should the pressure drop faster than it can be replenished by one pump, the second pressure switch 28 will out in the second pump when the pressure reaches a desired minimum.

It will be realized that the hereinbefore described forms of the invention are to be taken merely as preferred examples thereof and that various changes in size, shape and arrangement of parts may be made without departing from the spirit of the invention or the scope of the subjoined claims.

That which is claimed as new and is desired to be secured by Letters Patent of the United States is:

1. An oil pressure system of the character described comprising, a base, a pressure tank mounted on the base, a standpipe having apertures therethrough, said standpipe being mounted co-axially within said pressure tank and integrally connected to the top and bottom thereof t0 reinforce the tank, and means to introduce fluid into said standpipe tangentially thereof and adjacent the lower end to separate air from liquid.

2. An oil pressure system of the character described comprising, a base, a pressure tank mounted on the base, a standpipe having apertures therethrough, said standpipe being mounted axially within said pressure tank and integrally connected to the top and bottom thereof to reinforce the tank, and a pump mounted above said pressure tank to deliver fluid into said standpipe tangentially thereof and adjacent the lower end to separate air from liquid.

3. An oil pressure system of the character described comprising, a cylindrical base, a cylindrical pressure tank mounted on the base, said pressure tank including a fiat top and a flat bottom, a standpipe having apertures therethrough, said standpipe being mounted axially within said pressure tank and integrally connected to the top and bottom thereof to reinforce the tank, a plurality of reinforcing posts integrally connected to both the top and bottom of said pressure tank and spaced about the pressure tank between the standpipe and the periphery of said pressure tank, and means to introduce uid into said standpipe tangentially thereof and adjacent the lower end to separate air from liquid.

4. An oil pressure system of the character described comprising, a base, a cylindrical pressure tank mounted on the base, said pressure tank including a flat top and a flat bottom, a standpipe having apertures therethrough, said standpipe being mounted axially within said pressure tank and integrally connected to the top and bottom thereof to reinforce the tank, a plurality of reinforcing posts integrally connected to both the top and bottom of said pressure tank and spaced about the pressure tank between the standpipe and the periphery of said pressure tank, and a pump mounted above said pressure tank to deliver fluid into said standpipe tangentially thereof and adjacent the lower end to separate air from liquid.

JOSEPH KELLOGG.

REFERENCES CITED The following references'are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,567,148 Jennings Dec. 29, 1925 1,623,103 Frederick Apr. 5, 1927 2,228,401 Press'ler Jan. 14, 1941 2,347,472 Dorward Aug. 25, 1944 2,396,864 Logan Mar. 19, 1946 

